The latest release of Samba offers many new features including new password database backends not previously available. Samba version 3.0.0 fully supports all databases used in previous versions of Samba. However, although supported, many backends may not be suitable for production use.

The tdbsam backend provides an ideal database back-end for local servers, servers that do not need built-in database replication, and servers that do not require the scalability or complexity of LDAP. The tdbsam back-end includes all of the smbpasswd database information as well as the previously-excluded SAM information. The inclusion of the extended SAM data allows Samba to implement the same account and system access controls as seen with Windows NT/2000/2003-based systems.

The tdbsam backend is recommended for 250 users at most. Larger organizations should require Active Directory or LDAP integration due to scalability and possible network infrastructure concerns.

Redirection
With > you can forward the output of a command to a file (output redirection), with < you can use a file as input for a command (input redirection).

Pipe
By means of a pipe symbol | you can also redirect the output: with a pipe, you can combine several commands, using the output of one command as input for the next command. In contrast to the other redirection symbols > and <, the use of the pipe is not constrained to files.

Examples (Redirection):
1) To write the output of a command like ls to a file, enter

ls -l > filelist.txt

This creates a file named filelist.txt that contains the list of contents of your current directory as generated by the ls command.

However, if a file named filelist.txt already exists, this command overwrites the existing file. To prevent this, use >> instead of >. Entering

ls -l >> filelist.txt

simply appends the output of the ls command to an already existing file named filelist.txt. If the file does not exist, it is created.

2) Redirections also works the other way round. Instead of using the standard input from the keyboard for a command, you can use a file as input:

sort < filelist.txt

This will force the sort command to get its input from the contents of filelist.txt. The result is shown on the screen. Of course, you can also write the result into another file, using a combination of redirections:

sort < filelist.txt > sorted_filelist.txt

Example (Pipe):
If a command generates a lengthy output, like ls -l may do, it may be useful to pipe the output to a viewer like less to be able to scroll through the pages. To do so, enter

ls -l | less

The list of contents of the current directory is shown in less.

The pipe is also often used in combination with the grep command in order to search for a certain string in the output of another command. For example, if you want to view a list of files in a directory which are owned by the user tux, enter

Most people familiar with Linux have used the top command line utility to see what process is taking the most CPU or memory. There’s a similar utility called htop that is much easier to use for normal tasks.

htop is an interactive process viewer for Linux. It aims to be a 'better top': you can scroll the process list vertically and horizontally, and select a process to be killed with the arrow keys instead of by typing its process id. It requires ncurses

Comparison between htop and top
* In 'htop' you can scroll the list vertically and horizontally to see all processes and complete command lines.
* In 'top' you are subject to a delay for each unassigned key you press (especially annoying when multi-key escape sequences are triggered by accident).
* 'htop' starts faster ('top' seems to collect data for a while before displaying anything).
* In 'htop' you don't need to type the process number to kill a process, in 'top' you do.
* In 'htop' you don't need to type the process number or the priority value to renice a process, in 'top' you do.
* 'htop' supports mouse operation, 'top' doesn't
* 'top' is older, hence, more used and tested.

InstallationUbuntu users can 'upgrade' top to htop by installing htop using the Advanced Package Tool:

sudo apt-get install htop

OpenSuSe 11.2 users can use "1-click" installer to install htop - here
Once installed, just type htop at a terminal to launch it, and notice the great text-mode graph at the top of the display:

Here is the best part… just use your Up/Down arrow keys to select a process, and then you can kill it with the F9 key if you’d like, or you can change the priority by using the F7 and F8 keys. (note that you’ll have to be root to give anything really high priority).

TrueCrypt is a software system for establishing and maintaining an on-the-fly-encrypted volume (data storage device). On-the-fly encryption means that data is automatically encrypted or decrypted right before it is loaded or saved, without any user intervention. No data stored on an encrypted volume can be read (decrypted) without using the correct password/keyfile(s) or correct encryption keys. Entire file system is encrypted (e.g., file names, folder names, contents of every file, free space, meta data, etc).

Files can be copied to and from a mounted TrueCrypt volume just like they are copied to/from any normal disk (for example, by simple drag-and-drop operations). Files are automatically being decrypted on the fly while they are being read or copied from an encrypted TrueCrypt volume. Similarly, files that are being written or copied to the TrueCrypt volume are automatically being encrypted on the fly.

It's also possible to access the same encrypted partition/volume on multiple OSes, as long as they have TrueCrypt installed and are able to read the filesystem used on the disk. (So you still can't get at your ext3 filesystem on Windows!) This is particularly useful for encrypting the USB drive.

TrueCrypt Features:
* Creates a virtual encrypted disk within a file and mounts it as a real disk.
* Encrypts an entire partition or storage device such as USB flash drive or hard drive.
* Encrypts a partition or drive where Windows is installed (pre-boot authentication).
* Encryption is automatic, real-time (on-the-fly) and transparent.
* Parallelization and pipelining allow data to be read and written as fast as if the drive was not encrypted.
* Provides plausible deniability, in case an adversary forces you to reveal the password:
Hidden volume (steganography) and hidden operating system.
* Encryption algorithms: AES (256-bit key), Blowfish (448-bit key), CAST5 (128-bit key), Serpent (256-bit key), Triple DES, and Twofish ( 256-bit key) also supports cascading (eg, AES-Serpent-Twofish).

To play encrypted DVDs, the libdvdcss2 package is essential. libdvdcss2 is a simple library designed for accessing DVDs like a block device without having to bother about the decryption. More information about this package can be found at VideoLAN.

You can install libdvdcss2 as a 64-bit .deb package without installing the Medibuntu repositories:

If your build from source is successful, you can make a Debian (Ubuntu) package (.deb) for future use or can distribute to other users:

Install package tools: sudo apt-get install checkinstall

CheckInstall keeps track of all files installed by a "make install" or equivalent, creates a Slackware, RPM, or Debian package with those files, and adds it to the installed packages database, allowing for easy package removal or distribution.

Rebuild package using "checkinstall":

cd /path/to/extracted/package./configuresudo makesudo checkinstall

Keep the resulting ".deb" file for future use. It can later be installed using:

sudo dpkg -i packagename.deb

Note: These are basic instructions that may not always work. Some packages require additional dependencies and optional parameters to be specified in order to build them successfully. Also see these Ubuntu wiki instructions.

The most widely used command for monitoring log file is tail. Tail binary allows a user to watch the log file grow in realy time. Watching the log file grows can be done using an additional -f parameter. Alternatively, another approach to watch a log file grows can be done using tailf binary command.

Tailf:
tailf will print out the last 10 lines of a file and then wait for the file to grow. It is similar to tail -f but does not access the file when it is not grow-ing. This has the side effect of not updating the access time for the file, so a filesystem flush does not occur periodically when no log activity is happening.

tailf is extremely useful for monitoring log files on a laptop when logging is infrequent and the user desires that the hard disk spin down to conserve battery life.

The .daa file extension stands for 'Direct Access Archive' is a proprietary file format developed by PowerISO Computing for their CD/DVD image file-processing tool "PowerISO".

Unlike the majority of CD/DVD image formats, the PowerISO's .daa format allows advanced features such as file compression, password protection, encryption and the ability to split files in to multiple volumes. Due to these advanced features, PowerISO is the only software package that can read .daa files.

But it is very simple to convert DAA to ISO in linux. You just need an utility called daa2iso.

Install it on a RPM based system using ’sudo yum -y install daa2iso’
or on a debian based system using ’sudo apt-get install daa2iso.

And to use the utility, just type the following: daa2iso source-file.daa dest-file.iso

binchunker converts a CD image in a ".bin / .cue" format (sometimes ".raw / .cue") to a set of .iso and .cdr tracks. The bin/cue format is used by some popular non-Unix cd-writing software, but is not supported on most other CD burning programs. A lot of CD/VCD images distributed on the Internet are in BIN/CUE format.

The .iso track contains an ISO file system, which can be mounted through a loop device on Linux systems, or written on a CD-R using cdrecord. The .cdr tracks are in the native CD audio format. They can be either written on a CD-R using cdrecord -audio, or converted to WAV (or any other sound format for that matter) using sox. bchunk can also output audio tracks in WAV format.

Using bchunk:
Now enter the following command: bchunk
where the image.bin is the file that contains the actual data, image.cue is the catalogue file and basename is the name of the "output" that extracted files will go to. This command will create an iso image caled basename.iso

Enter the following comand: sudo mount -o loop basename.iso /mnt, this command will mount the iso file to /mnt

Wammu is a mobile phone manager that uses Gammu as its backend. It works with any phone that Gammu supports, including many models from Nokia, Sony-Ericssonn, Motorola, Samsung, Siemens, Huawei and others.

With all features above, i think Wammu can be an alternative for PC Suite-like application. Unfortunately, not all features above will work in any phone. You can find supported phone in Gammu’s Phone database. Find your phone in there before trying Wammu.

Services are programs (called daemons) that once started run continuously in the background and are ready for input or a changes in your computer and respond to them. For example the Apache server has a daemon called httpd (the d is for daemon) that listens on port 80 on your computer and when it receives a request for a page it sends the appropriate data back to the client machine.

Many services are required to run all the time however many can be safely turned off for both security reasons as running unnecessary services opens more doors into your computer, but also for performance reasons. It may not make much difference but your computer should boot slightly faster the less services it has to start on boot.

This post explains how to start/stop the services and how to control which services start automatically at boot time for Ubuntu System

The scripts located in /etc/init.d are part of the bootup sequence of every Debian-like distro. Very often Ubuntu's documentation and guides have suggested - in order to deactivate init scripts - to change the permissions of the scripts in /etc/init.d, making them non-executable. This will have the following consequences:

* You'll get an error message at boot time (to avoid it you need to patch all the scripts);
* You are breaking the logical chain stated in debian-policy concerning runlevel configuration.

If the logic of a debian-like system boot up sequence is not very clear and familiar to you, you should not play with symlinks, permissions, etc. In order to avoid messing up your system, Boot-Up Manager will automate all of your configuration in a nice and clean graphical interface.

The problem of the proprietary (closed source) drivers is a very important subject in those 2006 days. The openSUSE decided to follow the kernels developers recommendations and not to include proprietary drivers with the kernel.

The reasons why a certain drivers is not included in the main openSUSE are the following:

* The software is proprietary software, it does not conform to the Open Source definition.
* The software is providing functionality which is patented and the patent holder is preventing distribution of the software.
* The software violates laws concerning software distribution in jurisdictions where Novell conducts business.

Users who want to use this functionality despite this can follow this instruction to get the complete driver support in their OpenSuSe 11.2 Linux system.

NVIDIA Graphics Drivers:

The NVIDIA drivers cannot be integrated directly into openSUSE because of their license. Fortunately for new users, NVIDIA and openSUSE provide a very easy way to install NVIDIA drivers: NVIDIA makes RPMs for openSUSE and provides them in a repository.

Three classes of drivers support NVIDIA cards:

1. The open source “nv” driver which has severe limitations (does not even support some new cards like the Quadro 570FX, does not have proper dual head support and has no 3D support) It is included in Xorg and is used by default.
2. The closed source, proprietary “nvidia” driver which requires the “nvidia” kernel module which many kernel developers regard as being in violation of the GPL.
3. There is the reverse engineered nouveau driver which is based on the nv driver. It aims to provide proper dual head support and 3D support.

So, in order to get the driver support, download the following file depending upon your card and execute them to let YAST install and configure the driver for you.

1. X.org includes F/LOSS drivers for many (older) ATI graphics adapters. These are used by default.
2. The ATI graphics drivers are proprietary and many kernel developers consider this driver to violate the GPL license of the kernel.
3. ATI has released some register specifications of their recent chipsets but has not released any documentation about the 3D functionality of their newer cards. The new ativivo and radeonhd drivers support (alpha quality) newer ATI R500/R600 graphics adapters. See the corresponding openSUSE news item

Please, consider that many older ATI cards are supported very well by the standard free driver radeon, which is installed during installation.

OpenSuSe cannot include support for MP3 or DVD video playback or recording. MP3 formats are patented, and the patent holders have not provided the necessary licenses. OpenSuSe also excludes other multimedia software due to patent, copyright, or license restrictions, such as Adobe Flash Player and RealNetworks RealPlayer.

That doesn’t mean you can’t play .mp3 files in OpenSuSe , it just takes a bit of work (not much).

Follow these instructions to get mp3 and other multimedia support on your OpenSuSe 11.2.

Use "1-click" installer to install all the required Codecs pack

If you are using KDE - Download and run (execute) this
If you are using Gnome - Download and execute this
To enable DVD playback - Download and execute this

Openoffice.org for kids or better say OOo4kids is a project that aims to provide a simplified version of openoffice.org for kids between 7-12 years.

Ooo4Kids is based on OpenOffice.org source code. Everything is made with the idea to contribute back to OpenOffice.org Project, through OpenOffice.org Education Project, and students projects, but not only (all sort of contributions are welcome, of course). Resources are managed by the EducOOo non profit association.

The main difference between Open Office and Open Office 4 Kids are the missing features in Open Office 4 Kid. A benefit of this is the performance gain when working with Open Office 4 Kids compared to a default Open Office installation. The interface is different as well. Open Office 4 Kids makes use of less buttons in the interface and divides them into a header tool-bar and sidebar.Additional changes are planed by developers in future releases

OOo4kids is available for Linux ,Mac and Windows.The latest version of OOo4kids can be downloaded from this link : Here

iplist is a Linux application for blocking connections to and from a specified range of hosts using the netfilter netlink-queue library. Iplist is an open source IP filtering program similar to PeerGuardian for Linux.

Some typical reasons for using iplist are:
* to protect your privacy
* to ban a large number of unwanted clients
* to block whole countries or networks
* to block spam- and ad-servers
* for parental control
* network monitoring

Packets are filtered in the chains specified in IPTABLES_CHAIN_*. For each attempt to establish a new connection iplist looks at the source / destination address of the packet and decides based on the IPs in the lists whether to reject the connection (tcp-reset or icmp-port-unreachable) or to send it back to iptables to be handled by the rest of the iptables configuration. Packets in the INPUT chain are dropped by default. Nice side effects of rejecting packets rather than dropping are that there are no annoying timeouts if you try to access a blocked IP and it's hard to find out if the host which uses IPblock is online or uses a packet filter.

The Ubuntu Software Center is a virtual catalog of thousands of free applications available for Ubuntu — software to make your computer more useful. You can find applications by category or by searching, and you can install an application with the click of a button.

The Software Center also lets you examine the applications installed on the computer already,and remove those you no longer need.

To install a program from the Software Center, you need administrator access and a working Internet connection. start the application from Application ⟶ Ubuntu Software Center

In the Get Free Software section, find the program you want to install. If you already know its name, try typing the name in the search field. Or try searching for the type of program you want (like “spreadsheet”). Otherwise, browse the Software Center departments to find the program.

* Click the program in the list, and click the arrow button to go to the screen for the program.

* Click the Install button. You may need to enter your Ubuntu password before the installation can begin.

* How long a program takes to install depends on how large it is, and the speed of your computer and Internet connection.

While a program is being installed, it appears in the Software Center’s In Progress section. As soon as it disappears, the program is installed.

Modern computers do have internal clocks called Real Time Clock chips (RTC) that provide time and date information. These chips are battery backed so that even during power outages, they can maintain time but personal computers are not designed to be perfect clocks. Their design has been optimized for mass production and low-cost rather than maintaining accurate time.

For many applications, this is can be quite adequate, although, quite often machines need time to be synchronised with other PC's on a network and when computers are out of sync with each other problems can arise such as sharing network files or in some environments even fraud!

NTP can maintain time over the public Internet to within 10 milliseconds (1/100th of a second) and can perform even better over LANs with accuracies of 200 microseconds (1/5000th of a second) under ideal conditions.

Keeping Linux systems synchronized is highly important for many reasons such as:

To set up NTP time synchronization graphically, launch Time & Date, also available through (System ⟶ Administration ⟶ Time & Date). Click the keys to unlock settings. Now, you can select your time zone, and configure it to "Keep synchronized with Internet servers", at which point it will prompt you to Install NTP support.

After that, click "Select Servers" and check off the server closest to you.